FR2485603A1 - Nuclear raid and fall=out shelter - is made up of reinforced concrete hexagonal units placed next to one another with central post and concrete roof - Google Patents

Abstract

The nuclear shelter is made up of identical, hexagonal, reinforced concrete units which are joined to one another to form the desired layout. The thickness of the walls of the unit is pref. 35 cm and the thickness of the roof is 40 cm. A post (19) is pref. positioned in the middle of the unit to support the roof (3) during conditions of high external pressure. The roof (3) pref. houses a metallic tube (13) containing filtration material and seals which can be removed allowing the passage of e.g. a radio aerial.

Description

 SUMMARY OF THE TECHNICAL CONTENT OF THE INVENTION.

 Modules of predetermined shape intended to serve as shelters against conventional weapons, gas attacks (chemical or bacterial) and radioactive fallout. They can be constructed either in isolation or in groups, their shape being such that the grouping of several modules allows the combinations to be varied infinitely and responds to the protection of any number of individuals.

 These shelters are delivered completely finished, that is to say with the specific tools allowing them to meet their protective vocation.

 MAIN USES CONSIDERED.

 Although the invention relates to a form whose flexibility does not imply compliance with fixed general dimensions, the idea of leading to mass production has led to the search for two main modules of very specific objectives.

 The smallest module envisaged, "family module", corresponds to the protection of a family of 7 people.

 The other module, "collective module", will protect 25 people.

 INTEREST OF THE SHELTER SHAPE.

 The planar shape of our modules is that of a regular hexagon, analogous to the honeycomb cell. This type of cell lends itself to a name of infinite combinations since one can travel, by juxtapositions of similar modules, a path of any length whatsoever, bypassing all obstacles, spreading out in places with large plates cells attached to the assembly on all their faces, possibly closing in on itself, thereby improving the possibilities of evacuation.

 This shape, in plan, roughly corresponds to the minimum development of its perimeter for a given surface. Supplemented by an upper slab and a lower raft, it makes it possible to constitute a closed, massive box, thereby offering the optimum conditions for resistance to the effects of modern weapons.

 SHELTER STUDIES.

 The first quality of these shelters is their homogeneity, this is why we endeavored to remove any weak point and to study consequently the treatment of the openings.

 Another sought-after quality is the possibility of claiming recognized standardization.

 Since we did not have precise standards in FRANCE, we adopted the Swiss ITAP standards (Technical Instructions for the Construction of Private Shelters) which, in addition to the seriousness which is traditionally attacked by Swiss regulations, have the advantage of '' have enabled the creation in SWITZERLAND of an industry which has been able to develop standardized elements strictly in accordance with standards, controlled and guaranteed.

 However, these Swiss standards to which we formally refer, have been understood as defining minimums. Referring to the notice on "the development of emergency shelters against radioactive fallout" of June 1972, we have, on a number of points, overstepped.

 DESCRIPTION OF THE BASIC MODULE.

The basic module is made of reinforced concrete and schematically comprises three parts:
- A slab #, flat slab slightly overhanging the perimeter walls and poured on a suitable resistance ground. We take care that the bottom is as irregular as possible, contrary to the usual wanderings thus mobilizing the friction on the ground opposing the horizontal displacements.

 - Perimeter walls # shaped like a regular hexagon and having a thickness of 35 cm. of concrete.

- Finally, a roof whose thickness will vary from 40 cm. at the level of the interior walls Up to a maximum thickness in the middle of the structure, so as to create a slope allowing the flow of runoff water over the dome and at the same time offering the highest section resistant to maximum forces, bending caused by overpressures or depressions
- The walls are pierced with two openings. The first # serves as the main access door to the shelter, and will have one of the following dimensions
. 80 x I85 cm.

 . 100 x 185 cm.

 . 60 x I20 cm.

The second # opposite the first and measuring 60 x 80, will serve as an emergency exit.

- The two openings are closed, the first by a watertight armored door "PB", the second by an equally waterproof shutter, designated by "VB"
- This raft is in principle horizontal, but for large modules there is nothing to prevent a slight slope being given to it.

 HOMOGENEITY OF PROTECTION.

 The armored doors and shutters supplied by the Swiss industry, united form 20 cm. thick. Concrete filling, traditionally made of ordinary concrete, cannot therefore claim to provide protection equivalent to that of ordinary walls. This anomaly of Swiss standards is somewhat offset by the fact that Swiss shelters are almost always included in existing constructions: the door is therefore protected by the peripheral walls that surround it, but the shelters that we are projecting here, intended to be established outside, in a garden, in a park, etc. must imperatively present at the right of their doors, a protection of the same order as that of the walls. A fundamental characteristic of our shelters will thus be the use in these doors and in these armored shutters of high density concrete capable of ensuring resistance to external forces and, in particular to radiation, resistance equivalent to that of ordinary walls.

 To further protect this weak point of the front door, an awning slab covers it #. This slab is completed by # walls, either side or facing the door, so as to best respond to each particular case. A staircase # gives direct access to the main door.

Similarly, the opposite opening protected by the armored shutter leads to a reinforced concrete chimney # forming an emergency exit. It is equipped with galvanized steps and protrudes above the ground
The bottom of this fireplace is lined with draining materials. It is covered with a grid # preventing large materials from falling into the well.

VENTILATION - LIFE INSIDE THE SHELTER
The ventilation of the room will be ensured by means of fans of one of the four types homologous in SWITZERLAND S with signs by the name "VA" and adapted to the number of people that the shelter can collect. These ventilations accept the outside air by means of a pipe embedded in the concrete of the wall and open laterally in one of the cheeks of the opening of 60 x 80. The ventilators are equipped with a prefilter which can be sufficient in the cases Attack by conventional weapons. The air reception pipe after this prefilter can be connected to a carbon filter of appropriate size, and capable of retaining all the radioactive dust or gases which have managed to pass through the prefilter. These fans are electric fans for collective shelters and manual fans for family shelters. When they are fitted with an electric motor, this leads to the need for a diesel generator set located in the room with an external exhaust. In any event, all the fans can operate manually, the handling handle being long enough for two people to simultaneously operate it, the resistance to be overcome being able to be overcome quite easily by two children.

 In addition to this fundamental part, the shelter includes overpressure and vacuum valves (12 \), two-way operation being necessary since the overpressure following an explosion is followed by a vacuum against which it is also important to protect oneself. Any air intake and any exhaust are therefore provided with these valves forming an anti-blast valve.

 In addition to the following devices. defined by swiss standards, we foresee in the axis of the structure, in the cover slab, e, a metallic tube # leveled on the upper level of the ground - covering the structure. This tube, protected in its upper part by a thick sheet metal cap and, over its entire length by a material which it obstructs perfectly, receives, in the lower part, a plug which can be removed from the inside and on which alternatively, one can provide, for example, a hanging ring. It can be closed off from the inside: it therefore allows the passage of a long and fine object, radio Q antenna, rod supporting a signal, in the unlikely, but not impossible, assumption that both routes of exit would prove impractical. The possible launching of distress rockets would also be possible.

 ASSEMBLY OF MODULES.

 The basic cell being thus described, any assembly between two, three or more cells is possible. We can draw attention to the combinations which seem to be used most often and which are represented by the corresponding diagrams It is obvious that the possible assemblies are endless for example, the sketch # shows crament we can equip the land on which a complex is located, which can be a residential building as well as an administrative, school or other building. Different simple variants are shown on the sketches # (2 or 3 modules) # (4 modules) # (7 modules).

 All the solutions are possible for the common veil with two cells: establishment of a door called "pressure door" PB "or free bay of dimension at the choice of the user, while taking into account, however, the imperatives of resistance to pressures outside.

 In the hypothesis of assembling cells intended for the protection of a community it is natural to envisage a direct penetration from one of the buildings occupied by the population which it is a question of protecting; this avoids an exit to the outside and allows a layout of this access as convenient and as safe as possible.

 This direct access makes it possible, in particular, to create a decontamination hatch, necessary since the shelter is designed for a large number of people.

 In the hypo @@ é @ e or the @@@ és prin @ @ must remain outside, in accordance with the basic module that we have e @ ini above, the realization of this airlock of decontamination # is very simply by using the arrangement provided above the entrance it is only a question of completing the wall facing the door with a side wall, thickening these walls to the size of current walls, extending the slab awning preventing debris from falling in front of the main door.

 ADAPTATION OF BASIC MODULES TO SPECIAL SURPRESSIONS.

 What has just been described corresponds to shelters responding to the concern for protection against four types of danger: protection against conventional weapons, chemical or bacterial gases, and finally radiation.

 Mechanical protection, that is to say against the blast effect caused by conventional bombs and shells as well as by the atomic weapon requires, like protection against radiation3, great thicknesses of reinforced concrete. , if the protection against radiation does not lead to a possibility of exact determination of the thickness of the walls, the blast effect allows a quantitative calculation, The problem is that the Swiss standard imposes the possibility of choice between two pressures, a atmosphere or three atmospheres, this pressure being understood in reality as an overpressure, that is to say as the difference in pressure existing between the outside and the inside of the shelter.

 However, such a variation imposes. a priori, on shelters of geometry, different sizing of structures. Differences are embarrassing when the objective is to be able, from standard elements, to build shelters that meet various demands, including in terms of the overpressure to be admitted.

 One of the peculiarities of the patent is that the passage of an overpressure of one to three atmospheres, does not involve any modification of the construction system and is resolved by the simple out of a central post - in the middle of the room . It is this post which is represented in dotted lines on our sketches: #. It is added, quite anticipated - but this has no consequence in terms of execution - that in the hypothesis of the shelter with three atmospheres, the raft which remains cast in place, must be thicker under the wall peripheral and the; central post: 8, since the loads to be taken into account are almost tripled.

 POSSIBILITY TO BURIAL THE DEEP SHELTER SUITABLE FOR EACH CASE.

 A final feature of the project is that it is completely independent of the level of digging into the ground. In the absence of specific constraints, the "base" project provides that the volume of excavation imposed by the chosen depth is equal, taking into account the expansion, to the volume of embankment to be placed above and on the periphery of the structure.

But it stands to reason that nothing stands in the way
- the creation of a practically superficial shelter, except to find it a suitable seat on the ground, and except to admit the salient aspect of the earth nipple which will ultimately appear after its construction.

 - to bury the shelter completely and to cover it with such a thickness of soil as one chooses. The latter solution assumes that special attention is paid to the possible presence of water. In this hypothesis, the adaptation of the casing technique remains possible without calling into question the principles on which this patent application is based.

 INTERNAL ACCESS MARKETS.

 This possibility of water can lead to raising the level of the main entrance. I1 must then descend to the level of the raft.

 The interior access is then made by means of pre-manufactured steps 8 in the form of an inverted U-shaped box. These steps, cast from the same mold with a movable cheek # also include reserved holes # allowing their sealing from bolts with sticks, intended to hold them in place despite the effects of an acceleration caused by the effect of breath . These hollowed out steps serve as lockers for the storage of various goods and objects necessary for survival in the shelter.

 CONSTRUCTIVE DETAIL.

 If the two modules relate to two products which seem to respond to the two common problems, it is emphasized that the regular hexagon forming the basic cell remains homothetic to itself whatever the length chosen for the elementary side. We also note that the angles open at I20- are all similar and independent of the length of the side.

 One of the objectives is therefore to prefabricate the angles (an "outside" angle #E and an "interior angle #I in the form of angles open at 120) so as to form the walls with simple straight formwork # thus not presenting no subjection of keying with angle pliers always delicate.

Claims (5)

 1 CLAIMS  plane ì of surfaces of any shape.  to each other with or without communication so as to apply in  identical shutters, in regular hexagon shape, freely joined  nuclear, characterized by their constitution from elemen modules  1 Shelters for civil protection, against all weapons, including weapons 2 Shelters for civil protection, against all weapons, including weapons  nuclear, according to claim ND 1, characteristics for the possibility  dP3djunction in the center of the base module of a post allowing, without modi  fication of the general geometry, to accept different overpressures  those of the basic overpressure. 3 Shelters for civil protection, against all weapons, including tears  nuclear, according to claims l and 2, characterized by the existence  in the ceiling and in the center of the structure, a metal tube closed by a  filtration material and by two closure plugs, one at the top of the  tube, the other at its lower part, both removable and can be put back  in place after each use for intermittent communication  between the shelter and the outside world. 4 Shelters for civil protection, against all weapons, including weapons  nuclear, according to the preceding claims, characterized by the utility  sation, when necessary, of prefabricated access steps, fixed to the  body of the shelter and hollowed out to form storage space. 5 Shelters for civil protection, against all weapons, including weapons  nuclear, according to the preceding claims, characterized by the utility  sation of standard prefabricated parts allowing the realization of years  interior and exterior hexagon gles forming the basic module  whatever the dimension of the sides.